Edge seal strip for a tension screen

ABSTRACT

An elastomeric V-shaped seal strip for sealing between the edge of a material separating screen and a supporting side wall includes apertures which extend through the apex of the V to receive shafts of screen tensioning bolts. The shafts substantially bisect the angle formed between the diverging legs of the V to provide equal tensioning pressure for each leg. A concave sealing surface extending longitudinally along the length of the seal strip where the legs merge serves to seal against the edge of the screen. Convex sealing surfaces on the distal ends of the legs serve to seal against the side wall. The flexing butterfly shaped seal strip bridges the gap between the screen and side wall and allows tightening or loosening of the tensioning bolts without leakage of material from above the screen around its edges.

United States Patent Hubach et al.

[54] EDGE SEAL STRIP FOR A TENSION SCREEN [72] Inventors: Louis E.Hubach, Aurora; Edgar E.

Hardner, Willoughby, both of Ohio 52 user ..277/166,85/1JP,140/108,160/378, 209 402, 209/403, 209/408, 277/205 51 Int.Cl..B65d53/00,F16j15/00 5s FieldotSearch ..216/166,189,205;209/402,

[ 51 May30,1972

3,219,065 1 1/1965 Moeller ..209/403 FOREIGN PATENTS OR APPLICATIONS549,969 1/1957 Belgium ..209/402 Primary ExaminerHouston S. Bell, Jr.Attorney-Fay, Sharpe & Mulholland [5 7] ABSTRACT An elastomeric V-shapedseal strip for sealing between the edge of a material separating screenand a supporting side wall includes apertures which extend through theapex of the V to receive shafts of screen tensioning bolts. The shaftssubstantially bisect the angle formed between the diverging legs of theV to provide equal tensioning pressure for each leg. A concave sealingsurface extending longitudinally along the length of the seal stripwhere the legs merge serves to seal against the edge of the screen.Convex sealing surfaces on the distal ends of the legs serve to sealagainst the side wall. The flexing butterfly shaped seal strip bridgesthe gap between the screen and [56] References cued side wall and allowstightening or loosening of the tensioning UNITED STATES PATENTS boltswithout leakage of material from above the screen around its edges.1,296,275 3/1919 Firth ..85/1JP 2,566,777 9/1951 Schmidt ..277/189 5Claims, 5 Drawing Figures PAIENTEOmao I972 SHEET 1 BF 2 FIG. 2

INVENTORS. LOUIS E. HUBACH 6 EDGAR E GARDNER 4W 5W ZMJ/xolland ATTORNEYSBACKGROUND OF THE INVENTION This is a division of our co-pendingapplication for a Tensioned Screen With Seal, Ser. No. 786,670, now US.Pat. No. 3,557,953.

Machines for separating grain from fines are old in the art. A typicalcombination includes a plurality of decks of superposed screens and aseparate grain inlet for each screen at the entrance end thereof. Eachdeck includes a porous screen mounted above a non-porous pan. Grainflows from the inlet onto the screen and as it progresses, the finesfall through the screen onto the pan while the whole grains remain onthe screen.

Disposed at the discharge end of the screen and pan is a deflectingbaffle to deflect the separated grain to one side and the fines orforeign matter to the other side so that each deck will discharge itsseparated materials into separate vertically extending chutes.

Unfortunately, a plurality of problems arise in existing separatorswhich make separation of the materials difficult and cause the prior artdevices to be inadequate for the desired degree of clean grain requiredby modern standards. One of the problems is that the sealing devicesalong the edges of the screens have been inadequate to keep the grainfrom flowing into the lower pan section. The instant invention hasovercome this problem by providing a resilient seal of unique design forengaging the walls along the edges of the screen.

BRIEF DESCRIPTION OF THE INVENTION The seal includes an elongated stripof elastomeric material for abutting a substrate. The strip issubstantially V-shaped in cross-section and the projecting legs of theseal taper uniformly to greater widths as they converge toward the baseof the V. The extremities of the V-shape serve as plural sealingsurfaces. A plurality of apertures extend perpendicularly through theapex of the V to receive bolts which hold the seal strip in operativeposition.

The grain separating combination of the screen, tensioning means for thescreen and the seals at each side edge of the screen is assembled in thefollowing arrangement; a screen for separating grain is held tautbetween two walls of a vibrating apparatus; hook strips are formed aslongitudinal pockets to receive the two side edges of the screenadjacent the walls; the hook strip is then folded to provide a clampingaction on the screen edges; extending through the hook strip and thescreen are a plurality of aligned apertures which in turn are alignedwith the apertures in the seal strips and openings through the walls;and threaded T-bolts extend through the aligned apertures. Conventionalnuts are threaded onto the shank of the T- bolts which extend throughthe walls. To make the screen more taut, one need only tighten the nutson the various T- bolts against the walls. The seal strip is designed tosealingly conform to the shape of the outer edge of the hook strip andto project into flexing sealing engagement with the side wall of thescreening apparatus.

It is an object of this invention to provide a seal having a concavesealing surface and including at least two convex sealing surfacesthereon.

It is another object of this invention to provide a seal having aconcave surface facing the side wall of a vibrating apparatus andlocated between a screen and the wall.

It is another object of this invention to provide a seal with anaperture therethrough for receiving an anchoring means such as a T-bolt.

It is another object of this invention to provide in combination ascreen suspended between two walls, a V-shaped seal between the wallsand the screen and means for tensioning the screen.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagrammatic view of a boxand shaker apparatus in which the invention is incorporated;

FIG. 2 is a fragmentary elevational view showing the incorporation ofthe screen member in the plurality of decks in the box;

FIG. 3 is a cross-sectional elevational view in section of thetensioning means for the screen;

FIG. 4 is a modification of FIG. 3; and

FIG. 5 is an exploded view of the seating tensioning combinationcomprising the invention.

PREFERRED EMBODIMENT in grain separating apparatus as shown in FIG. 1, amultideck separator incorporating this invention is indicated generallyat 10 and includes two boxes or housings l2 and 14. An eccentricallymounted shaker or vibrator means 16 is disposed between the housings anda plurality of resilient mountings 18 at the comers support thevibrating apparatus.

Disposed within each housing as illustrated in FIG. 2, are a pluralityof screening decks indicated generally at 22. Each deck includes ascreen 24 and a pan 26 with upturned edges 25. Wooden spacer bars 27extending the length of the screen are provided as needed. The means forvibrating 16 causes any grain deposited on he screen to be agitatedwhereby small grains, foreign matter and pieces of broken grain willpass through the pores of the screen and fall on the pan 26.

As best seen in FIGS. 3, 4 and 5, the screen is held in tension betweenthe side walls of the vibrating apparatus by a plurality of T-bolts 28.While T-bolts are described and preferred, L shaped bolts may be usedsatisfactorily. The edge of the screen 24 is confined in a pocket 30formed by a hook strip element 32. After the screen is received in thepocket 30, the hook strip is folded to crimp the screen 24 therein.

Aligned apertures 34 and 36 in the hook strip and screen, respectivelycircumscribe the T-bolt 28 which includes a cross piece 40 and athreaded shank portion 42. The shank extends through the screen and hookstrip apertures 34 and 36, respectively. It further projects through anaperture 44 in the side wall 46 into threaded engagement with a lock nut47 and a tensioning nut 48 which clamp a washer 49 against the sidewall.

Because it is undesirable to have the whole grains on the upper portionof the screen passed to the pan 26 during the vibrating and shakingoperation, an elastomeric seal strip 50 is provided at each edge of thescreen. The seal strip is substantially V-shaped in cross-section withthe legs of the V tapering uniformly to greater widths as they convergeinwardly toward the apex of the V and at their outer ends they terminatein rounded sealing surfaces 52. The rounded surfaces 52 allow for easiertranslation along the wall 46 when the screen is tightened or loosened.

The merging of the legs of the V at its apex includes a concave sealingsurface 56 which is shaped to conform to the edge of the hook strip 32.The concave surface 56 is best seen in FIG. 5 and its confomiing shapeis best illustrated in FIGS. 3 and 4. As can be seen, when nuts 47 and48 are tightened the bolt 28 will push the seal strip 50 toward theupturned edge 25 on the pan and the side wall 46. Because the seal strip50 is symmetrically arranged about the shank 42 of the bolt, tighteningof the nuts will uniformly increase the sealing effectiveness of theseal strip; the legs of the strip will open wider and push harderagainst the wall and this in turn will cause the concave sealing surface56 to scissor into a tighter grip on the edge of the screen 24. It isobvious that without the symmetrical design which provides equal andopposite forces within the seal it would not be as effective as it is inthis application. Thus, the unique butterfly design provides superiorsealing, compared to other designs on the market.

It should be noted that each of the three curved sealing surfaces 56 and52 has an axis and that the three axes are substantially parallellyaligned along the seal strip. In addition, the axes of the apertures 58through the strip extend substantially perpendicular to the axes of thesealing surfaces. It is intended that the apertures 58 intersect theconcave sealing surface 56 whereby the aperture axes and the sealingsurface axis intersect. Differently stated, intersecting planes whichpass through the axis of the concave sealing surface and one of the axesof one of the convex sealing surfaces define an angle, which angle issubstantially bisected by the axes of the apertures 58. This featureinsures the aforementioned symmetrical forces within the seal strip.

While the method of forming the seal strip is immaterial to thisinvention, it could be thought of as two similar or mirror imageelastomeric strips joined along one end to form a concave sealingsurface for sealing against the separator screen.

Each distal end of each of the joined strips includes a convex sealingsurface for sealing against the supporting wall.

The drawings show the outer extremities of the seal 50 engaging theupturned edges 25 of the pan. This is the preferred embodiment. But,notwithstanding the unitary nature of the preferred embodiment, theupturned edges 25 may be eliminated if desired and the seal 50 maydirectly contact the vertically extending side wall or substrate 46 ofthe housing 12. Such elastomeric strips 50 could also be providedbetween the pan 26 and the substrate 46. In the embodiments illustrated,an aperture 57 through the upturned edge 25 is aligned with the hookstrip and wall apertures.

Extending through the V-shaped seal 50 and perpendicular to the apex ofthe V is an aperture 58 which circumscribes the T-bolt. The legs of theseal strip straddle the wall opening 44 and in this manner help toprevent any outside foreign matter from being incorporated in thecleaned grain or separated fines on the pan from escaping the boxes 12and 14. The improved benefits of the sealing apparatus are easily seenby observing FIGS. 3, 4 and 5. The V-shape of the seal allows foradjustment of the T-bolt for greater tensioning or for loosening, whilethe extreme ends of the V-shaped seal strips still engage and sealagainst the walls. The easy flexing of the elastomeric material allowsfor less stringent manufacturing tolerances as to the width of thescreen and the crimping and folding of the hook strip.

FIG. 4 shows a modification of the shape of the hook strip. Thepreference as to shape usually depends upon the particular material tobe separated. In FIG. 3 the edge 60 of the hook strip extends above thecross piece 40 of the T-shaped bolt, while in FIG. 4 the fold of thehook strip material places the edge 62 below the cross piece.

For ease of description the principles of the invention have been setforth in a single embodiment. It is not intended that the illustratedembodiment nor the terminology employed to describe it be limiting. Onehaving ordinary skill in the art will be aware of several modificationswithin the spirit of this invention. Rather it is intended that anyrestrictions on the invention be limited only by the appended claims.

The invention claimed is:

1. An elongated elastomeric seal strip for use in screening and materialseparation machines, said strip being designed for location between thesidewall of the machine and the edge of a screen within the machine, thescreen being placed in tension by bolts projecting from the screenthrough the sidewall where nuts are tightened to regulate said tension,said seal strip being designed to prevent material located above thescreen from passing below the screen without passing through the poresthereof by the locations of one sealing surface for engaging the screenedge and two sealing surfaces for engaging the sidewall, the seal stripcomprising,

an elongated substantially V-shaped strip with three sealing surfaces,one sealing surface being on the outer surface of the apex of the V andthe other two being at the extreme ends of the two legs,

the inner and outer surfaces of each of the legs converge toward theextreme ends, said extreme ends being rounded in a smooth convex curveconnecting the converging inner and outer surfaces, said rounded extremeends comprising two said sealing surfaces,

the sealing surface at the apex for sealing against the screen edge comrisingl a smooth concave groove extending the length of t e se strip,said groove being located symmetrically with respect to the V-shape andthe thickness of the seal strip at the bottom of the groove being lessthan the thickness of either leg immediately adjacent the groove.

2. The seal strip of claim 1 including a plurality of apertures throughthe seal strip, said apertures being adapted to receive the bolts andbeing substantially perpendicular to said groove.

3. The elastomeric seal strip of claim 1 wherein each of the threesealing surfaces defines a smooth curve having an axis, the three axesbeing substantially parallel to each other,

each a erture having an axis substantially perpendicular to the axis ofthe concave sealing surface.

4. The elastomeric seal strip of claim 1 wherein the axes of saidapertures substantially bisect the angle formed by two intersectingplanes, each plane passing through the axis of the concave sealingsurface and the axis of one of the convex sealing surfaces.

5. The seal strip of claim 2, wherein the diameter of the apertures isless than the width of the groove.

UNITED STATES PATENT OFFICE I CERTIFICATE OF CORRECTION Patent No. 3, 77Dated y 3 97 Inventor(s) Louis E. Hubach 8t Ell It is certified. thaterror appears in the above-identified patent and that said LettersPatentare hereby corrected as shown below:

On the cover sheet [72] the name of the inventor "Edgar E. Hardner"should read Edgar E. Gardner Signed and sealed this 7th day of November1972 (SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GOITSCI-LALK Attesting Officer Commissionerof Patents ORM PO-105O (10-69) USCOMM-DC BO376-P69 U.S, GOVERNMENTPRINTING OFFICE: 1959 D365-334.

1. An elongated elastomeric seal strip for use in screening and materialseparation machines, said strip being designed for location between thesidewall of the machine and the edge of a screen within the machine, thescreen being placed in tension by bolts projecting from the screenthrough the sidewall where nuts are tightened to regulate said tension,said seal strip being designed to prevent material located above thescreen from passing below the screen without passing through the poresthereof by the locations of one sealing surface for engaging the screenedge and two sealing surfaces for engaging the sidewall, the seal stripcomprising, an elongated substantially V-shaped strip with three sealingsurfaces, one sealing surface being on the outer surface of the apex ofthe V and the other two being at the extreme ends of the two legs, theinner and outer surfaces of each of the legs converge toward the extremeends, said extreme ends being rounded in a smooth convex curveconnecting the converging inner and outer surfaces, said rounded extremeends comprising two said sealing surfaces, the sealing surface at theapex for sealing against the screen edge comprising a smooth concavegroove extending the length of the seal strip, said groove being locatedsymmetrically with respect to the V-shape and the thickness of the sealstrip at the bottom of the groove being less than the thickness ofeither leg immediately adjacent the groove.
 2. The seal strip of claim 1including a plurality of apertures through the seal strip, saidapertures being adapted to receive the bolts and being substantiallyperpendicular to said groove.
 3. The elastomeric seal strip of claim 1wherein each of the three sealing surfaces defines a smooth curve havingan axis, the three axes being substantially parallel to each other, eachaperture having an axis substantially perpendicular to the axis of theconcave sealing surface.
 4. The elastomeric seal strip of claim 1wherein the axes of said apertures substantially bisect the angle formedby two intersecting planes, each plane passing through the axis of theconcave sealing surface and the axis of one of the convex sealingsurfaces.
 5. The seal strip of claim 2, wherein the diameter of theapertures is less than the width of the groove.